export default class DropdownLinkage extends HTMLElement {
    private dom;
    private province_node;
    private city_node;
    private district_node;
    private myDB;
    private attrs;
    constructor();
    connectedCallback(): Promise<void>;
    get_selected(): {
        city_name: string;
        city_no: string;
        district_name: string;
        district_no: string;
        province_name: string;
        province_no: string;
    };
    set_selected(province_no?: string, city_no?: string, district_no?: string): void;
    private initialize;
    private is_init;
    private check_attribute;
    private render_initialize;
    private render;
    private insert_data;
    private render_select;
    private post;
}